Research On Basic Model And Control Strategy Of Frequency Situation Awareness In Complex Power System

At present,power system has large scale and complex structure.The penetration rate of renewable energy is increasing,the load is more scattered and diverse.Therefore,the traditional System Frequency Response(SFR)model can’ t analyze and predict the developing condition of power system’ s frequency accurately,the frequency stability control measures based on SFR model can’ t control power system frequency stably.Based on this,this paper studies the basic frequency situational awareness model of power system and the frequency control strategy under multi-energy.Firstly,this paper studies the basic frequency situational awareness model of power system under multi-energy integration.The model aggregates the important parameters(inertia time constant,adjustment coefficient,damping factor,etc.)of wind,water and fire power generator units equivalently,then added turbine speed control and virtual inertia links of the fan in the traditional SFR model,set the proportion coefficients of different generator-speed regulators to get the frequency situational awareness model.Combined with the frequency situational curve,the parameters in the model are corrected by quadratic optimization algorithm,which improves the perception accuracy of the frequency model.Secondly,the system frequency stability can be analyzed according to the frequency situational awareness structure introduced above,combined with the binary table of the power unit’ s frequency stability operation range,makes frequency offset and offset operation the key elements,the fast frequency stability evaluation index is presented.Then this paper puts forward a high frequency shutdown strategy based on the basic system frequency situational awareness model and fast frequency stability evaluation index for the blocked delivery channel of Sichuan power network.Then,according to the power plant capacity and reserve capacity to get the required cutting capacity,set influence factor for the actual transmission performance of the line,give the priority of unit cutting according to the importance of different generators and add active power additional coordinated control measures such as DC modulation to improve the accuracy of frequency control.Finally,IEEE 9 nodes is simulated to verify that the basic frequency situational awareness model can accurately predict power system frequency under different operating conditions.PSASP Sichuan power network simulation example validates that the high-frequency cutting strategy can make the frequency stable,the speed is faster and the effect is better than the traditional one.The research results of this paper have important value for the stable frequency operation and control of large-capacity delivery system.